# Impact of risk adjustment for drug-resistant types on tuberculosis patients’ outcomes under China’s innovative payment methods: a quasi-experimental study design

## TL;DR

This study examines how adjusting payment methods for drug-resistant tuberculosis in China affects patient outcomes and healthcare costs.

## Contribution

The study introduces a novel risk adjustment policy in China's payment system for tuberculosis, showing its impact on resource use and treatment efficiency.

## Key findings

- Risk adjustment led to reduced out-of-pocket costs and shorter hospital stays for TB patients.
- The policy improved efficiency for drug-susceptible TB patients without harming care quality for drug-resistant cases.
- No significant changes were observed in outcomes for drug-resistant TB patients.

## Abstract

Treating drug-resistant tuberculosis (DR-TB) is clinically complex and economically burdensome compared to drug-susceptible tuberculosis (DS-TB). China’s diagnosis-intervention packet payment system initially omitted risk adjustment for drug resistance. In 2022, a diagnosis-intervention packet (DIP)-pilot city implemented such adjustment, establishing distinct reimbursement standards for DR-TB and DS-TB. This study aimed to assess the impact of this DR-type risk adjustment on medical expenditures, treatment efficiency, and care quality for TB patients.

A quasi-experimental difference-in-differences design was employed, involving 8465 TB patients from June 2021 to December 2023. Linear regression was performed with time and treat fixed effects and the interaction term between time and treat. Subgroup analyses for DR-TB and DS-TB patients were conducted.

Under the DIP system, risk adjustment led to marginally significant reductions in inpatient expenditure per hospitalization [β = − 151.14, P = 0.065; 95% confidence interval (CI) for difference in proportions: − 311.66, 9.38] and in annual total inpatient expenditure per patient (β = − 200.58, P = 0.078, 95% CI − 423.26, 22.10) for all TB patients. It also resulted in significant reductions in inpatient out-of-pocket per hospitalization (β = − 257.51, P < 0.001, 95% CI − 316.20, − 198.81), annual total inpatient out-of-pocket per patient (β = − 266.78, P < 0.001, 95% CI − 342.02, − 191.53), inpatient length of stay per hospitalization (β = − 3.58, P < 0.001, 95% CI − 4.53, − 2.62), and annual total length of stay per patient (β = − 3.21, P < 0.001, 95% CI − 4.50, − 1.92). For DR-TB patients, all outcome measures in expenditures, efficiency, or care quality showed P > 0.1, indicating no significant changes. For DS-TB patients, measures of expenditures and efficiency showed P < 0.1, supporting significant or marginally significant reductions.

The DR-type risk adjustment policy under China’s diagnosis-intervention packet system proved effective in optimizing resource use and enhancing efficiency, particularly for DS-TB patients, while preserving care quality for DR-TB patients. These findings demonstrate the value of tailored risk adjustment within payment frameworks for heterogeneous diseases like tuberculosis, providing crucial evidence for optimizing TB care and implementing effective payment reforms in China and similar settings.

The online version contains supplementary material available at 10.1186/s40249-026-01423-y.